This invention relates in general to vehicular wheels and, more particularly, to a unitary wheel and tire assembly.
Heretofore in the toy field it has been the practice of molding a wheel entirely of rubber, or of molding a relatively non-elastic tire to a wheel. Such assemblies have admittedly been useful only for toys and miniature models so that limited wear and scarcely minimum stresses have been encountered.
With wheels of larger character for practical usage, such as with industrial carts of all type, as well as with vehicle frames adapted to support substantial weight, there have only been utilized independently formed tires mountable upon the wheel by various conventional well known mechanical expedients. Understandably, wheels and tire assemblies of the last mentioned character have been relatively costly, both in production, as well as in use.
Therefore, it is an object of the present invention to provide a unitary wheel and tire assembly comprising a wheel molded of thermoplastic resin and having a resilient, wear-resistant tire molded directed thereupon, which assembly is capable of versatile practical usage, such as, for example, with industrial carts of all types, small tractors, lawn mowers, etc., and thus being of diameters considerably greater than wheels used on toys and miniature models.
It is another object of the present invention to provide an assembly of the character stated which comprehends a wheel having an irregular exterior surface for effecting an intimate, tenacious, mechanical bond with confronting internal surface portions of the tire.
It is a further object of the present invention to provide a unitary wheel and tire assembly wherein the tire possesses markedly elastic characteristics, having a high coefficient of friction and thereby conducing to excellent traction.
It is a still further object of the present invention to provide a unitary wheel and tire assembly wherein the wheel may be foam-molded for enhancing the strength thereof, as well as bringing about substantial economies in the cost of production.
It is another object of the present invention to provide a unitary wheel and tire assembly which, as stated, is adapted for wide application; which is reliable and durable in usage, being resistant to accidental parting of the tire under stress-producing conditions, including developed radially applied forces; and which by its simplicity, is amenable to low cost, high volume manufacture.
It is a still further object of the present invention to provide a method for producing a unitary wheel and tire assembly which may be most economically accomplished by currently available equipment.